The present invention relates to an ignition cable for use in motor vehicles such as automobiles.
Noise suppressing high tension resistive electrical wires comprising reinforcing cords about which metallic resistive wires are wound and subsequently provided with insulation coatings have been used as ignition cables in automobiles.
A conventional type of such high tension electrical wires has the composition shown in FIG. 2. A reinforcing cord 5a formed of a bundle of fine, high-strength fibers such as glass fibers or Aramid fibers is provided with an extruded coating layer 5b of such a material as a ferrite powder filled silicone rubber. A fine metallic resistive wire 5c made of a Ni-Cr alloy or the like is wound around the coating 5b to form a conductor winding 5. This conductor 5 is wrapped with an insulating rubber coating layer 6, a glass fiber braid 7 and a sheath 8 to form a high tension resistive electrical wire. A ignition cable is fabricated by installing a metallic terminal on both ends of the resistive wire.
The high tension resistive electrical wire employing a conductor winding of the type described above ensures consistent performance but has the disadvantage of increased thickness.
Car manufacturers are making active efforts to furnish their products with an increasing number of capabilities in engine rooms and as the density of components installed in the engine room increases, it becomes more and more difficult to harness the wiring of ignition cables over the shortest distance. However, the conventional noise suppressing high tension resistive electrical wires which are thick and difficult to bend involve considerable difficulty in harnessing the cables in small spaces. It has therefore been desired to develop a noise suppressing high tension resistive electrical wire that is finer and which can be bent at a smaller radius of curvature.